Produced water’s benefits for the oil and gas industry

Reusing produced water can improve production and lessen environmental impact.

By William DiCroce, Veolia North America May 10, 2018

Access to clean water is essential to support all life on Earth. Besides the human need for it, water is used to irrigate crops, manufacture goods, and even obtain the oil and natural gas used for fuel and to help generate energy.

The truth is, where there is oil, there is water. As the upstream U.S. oil & gas industry expands, larger volumes of the water are extracted in the process of producing oil and gas. This so-called produced water needs to be sustainably managed.

Water scarcity is a real challenge that will, at some point, affect everyone. Though once thought to be cost-prohibitive, the sustainable management of produced water offers both a solution and opportunity to the oil & gas industry.

Produced water generated from the oil & gas extraction process contains impurities. It is therefore not suitable without purification for direct discharge to surface waters. Historically, produced water was disposed through injection into dedicated Class II saltwater disposal (SWD) wells. Yet, with U.S. crude production now estimated at more than 10 million barrels per day, the total volume of produced water could far exceed the capacity of available SWD wells. In addition, with public attention focused on the seismic activity associated with injection, produced water is a bottleneck for operations across the industry.

The good news is, by teaming proprietary technology with operational excellence, we can treat produced water and remove contaminants for reuse and surface discharge, eliminating this major production bottleneck in a compliant, cost-effective, and environmentally friendly way.

One way to limit SWD well injection is to treat produced water for surface discharge. Produced water is treated with proprietary technology for removal of undesired contaminants, generating fresh water that meets the standards for safe surface discharge, as established by local and federal governments. In meeting these requirements, studies show that treated water can be reused beneficially for agriculture, irrigation, steam generation, hydraulic fracturing, and more.

In fact, in California, multiple oilfields already sustainably manage produced water to minimize SWD well injection. These projects purify produced water for reuse in steam generation and surface discharge. The result is minimized environmental impact on water-stressed California. An end-to-end solution delivers value to a production process while also mitigating a primary public concern surrounding water scarcity and seismic activities.

Producers need to realize they can reuse produced water in their operations as well as recover valuable byproducts from produced water, including fresh water, sodium chloride (NaCl), and calcium chloride (CaCl2).

Whenever the oil & gas industry can reuse water that would have otherwise been deemed as "waste water," it is a win-win for the industry and the environment. 

William DiCroce is the president and CEO of Veolia North America

Original content can be found at Oil and Gas Engineering.